He thanked the manager for believing him to accomplish this task with efficiency.
He thanked the manager for believing in him to accomplish this task with efficiency.
Is is necessary that the preposition in has to be placed between believing and him?
I thought believe can take a object, so the preposition here doesn't seem necessasry,
but it was marked wrong and in was added to it.
By the way, with the preposition in,
the implied subject of the infinitive to accomplish this task with efficienct is still him, am i right?
